1. Field of the Invention
The present invention relates to a mirror device to be fixed to a vehicle. More specifically, the present invention relates to a manual mirror device configured to be capable of turning a mirror between an operated position and a folded position by manual operation.
2. Description of the Related Art
As shown in FIG. 1, a manual mirror device 100 includes a mirror base 110, a plurality of screws 120, a shaft 130, a housing 140, a plurality of balls 150, a push nut 160, and a compression coil spring 170.
The mirror base 110 is made of resin and is fixed to a vehicle, more specifically, a car door. The shaft 130 is made of metal and has a lower portion to be fixed to the mirror base 110 by the screws 120. Also, the shaft 130 has an upper portion which penetrates a lower portion of the housing 140 to be housed in the housing 140. The housing 140 is made of resin and has a mirror unit (not shown) with a mirror in the interior of thereof The balls 150 are disposed between the housing 140 and a base portion 131 of the shaft 130. When the housing 140 is manually operated, the housing 140 turns around the shaft 130 by use of the balls 150. In this event, the balls 150 reduce friction between the base portion 131 and the housing 140.
In addition, the housing 140 attaches the balls 150 by pressure to the base portion 131 by use of the push nut 160 and the compression coil spring 170. The push nut 160 is fitted into a spindle 132 of the shaft 130. The compression coil spring 170 is disposed and compressed between the housing 140 and the push nut 160. In this configuration, the housing 140 attaches the balls 150 to the base portion 131 by elastic force of the compression coil spring 170. Accordingly, the housing 140 turns around the shaft 130 without wobbling.
However, in the manual mirror device 100, the number of components is increased because the screws 120 are applied to fix the shaft 130 to the mirror base 110. Also, an assembly operation is complicated because there is an operation for screwing the screws 120 into the mirror base 110 and the shaft 130.
As a device to solve the foregoing problems, Japanese Unexamined Patent Publication No. 9(1997)-99780 discloses a manual mirror device 180. As shown in FIGS. 2 to 4, the manual mirror device 180 includes a mirror base 190, a shaft 200, a housing 210, a mirror unit 220, a plurality of balls 230, washers 240, a push nut 250, a compression coil spring 260, and a clip plate 270.
The mirror base 190 is made of resin and has an L-shaped cross section. The mirror base 190 has a fixing portion 192, a base portion 194, and hole portions 196. The fixing portion 192 is fixed to a vehicle, more specifically, a car door. The base portion 194 is connected to a lower side surface of the fixing portion 192. The hole portions 196 are formed on an upper surface of the base portion 194.
The shaft 200 is made of an aluminum alloy or the like, and has a lower portion to be fitted to the base portion 194. Also, the shaft 200 has an upper portion which penetrates a lower portion of the housing 210 to be housed in the housing 210. The mirror unit 220 is fitted to the housing 210 so as to occlude an aperture of the housing 210 with a mirror 222. Angular adjustment of the mirror unit 220 is achieved by manual control through a pivot mechanism (not shown), remote manual control through a wire, a controller knob (not shown) and the like, or remote control through a power unit mechanism (not shown).
As shown in FIG. 4, the shaft 200 has a flange 202, a spindle 204, and convex portions 206. The flange 202 abuts on a lower surface of the base portion 194 of the mirror base 190. The spindle 204 extends upward from the flange 202 to penetrate the base portion 194 and the lower portion of the housing 210. The convex portions 206 are formed in a plurality of positions (in three positions) on a circumference of the flange 202. The hole portions 196 are formed on the base portion 194 in positions to be opposed to the convex portions 206 in the state where the shaft 200 is fitted to the mirror base 190. The shaft 200 is fitted to the mirror base 190 so as not to turn relative to the mirror base 190 by fitting the convex portions 206 into the hole portions 196, respectively.
The convex portion 206 of the shaft 200 has a dent on an upper surface thereof. The washers 240 are made of either hard resin or metal, and are fitted into the lower portion of the housing 210 in positions to be opposed to the convex portions 206 in the state where the shaft 200 penetrate the lower portion of the housing 210. Each washer 240 has a dent on a lower surface thereof. One part of the ball 230 is fitted into the dent of either the convex portion 206 or the washer 240. In the state where the convex portions 206 are respectively fitted into the hole portions 196, the housing 210 turns around the shaft 200 by use of the balls 230 if the housing 210 is manually operated. In this event, the housing 210 is temporarily fixed to the mirror base 190 when the balls 230 are housed in the dents of either the washers 240 or the convex portions 206.
The housing 210 attaches the balls 230 by pressure to the base portion 194 of the mirror base 190 or the convex portions 206 by use of the push nut 250, the compression coil spring 260, and the clip plate 270. The push nut 250 is fitted into an annular engaging groove 208 formed in the spindle 204. The clip plate 270 is formed of a metal washer and is fixed to an upper surface of the lower portion of the housing 210. The compression coil spring 260 is disposed and compressed between the push nut 250 and the clip plate 270. In this configuration, the housing 210 attaches the balls 230 to the base portion 240 or the convex portions 206 by elastic force of the compression coil spring 260. Accordingly, the housing 210 turns around the shaft 200 without wobbling. Moreover, since the shaft 200 is fixed to the mirror base 190 by the elastic force of the compression coil spring 260, it is not necessary to use screws.
However, in the manual mirror device 180, the number of components is increased because the washers 240 are fitted into the lower portion of the housing 210 to reduce friction between the balls 230 and the housing 210. Such an increase incurs a weight increase of the device and complication of an assembly operation. Moreover, the dents formed on the convex portions 206 and on the washers 240 incur complication of a processing operation.